Okay... so I am ready to wire three Simer pumps. I bought some switches that have three posts on back for on/off/on and a post for the lights, total of four posts. Will these work and how do I wire them? If not what swithes do I need? Also, I need to get a plate or panel to mount them in... any suggestions? Thanks!

You can use DPDT, 6-pin switches. You can wire them up straight from battery to fuse to switch to pump, but if your wire runs are more than a few feet and you want to run all three pumps at the same time, you may want to use relays to keep the runs from your batteries to the pump as short as possible. And/or use very large wire. The Simers draw a lot of current, especially when they spike at turn-on. Turn them on one at a time.

Sorry, those aren't going to work if you want to wire them reversibly. On/off/on means it's the same polarity being sent out for both directions of the switch. You need a reversible 6 or 7 pin switch for each pump. I did a quick search and came up with this thread to detail the wiring. http://forums.wakeboarder.com/viewtopic.php?t=7670